2000 S40 - Won't Start Without Foot on Gas

AGSchear · Post by **AGSchear** » 06 Oct 2012, 22:07

My trusty S40 didn't want to start today after driving to my Little's house to pick him up. The car failed to turn over unless I put my foot on the gas. It would start up great if I did that, but then stall out immediately if I took my foot off.

The car started and ran fine driving to his house, and I didn't expect it to fail to start. For some time now, the car has had long crank times (5-8 seconds) and seems like it takes quite a bit to turn over. I also get a hint of gasoline odor coming from the exhaust when starting, but at no other time. The car has an intermittent rough idle, but lately it has been happening less. When it's cold, it is sometimes a little sluggish to respond. I've posted about these issues before, but have done a number of fixes to seem to make things a little better every time.

I ran the computer and got P0102 and P0107. From my searches I'm led to believe these codes have to do with an MAF sensor having low voltage and an MAP sensor.

From my searches of my main symptom, I have learned that the problem may have to do with the Fuel Pressure Regulator or the IAC valve.

The car has 131,000 miles on it. I changed the oil a couple hundred miles ago and the level looks perfect. I replaced the plugs, coils, and wires about 6 months ago and the new ones seem to be working great. I cleaned the IAC valve a month ago (it was filthy) and have driven the car about 1,000 miles without issue. I replaced the battery 15 months ago with a NAPA 10 year model.

I have a friend who is a mechanic that has offered to take a look at the car tomorrow. It has been suggested by my father and my Little's father that I have an issue with the fuel filter, but from my research I think it's something under the hood in the FPR/IAC area. If anyone can offer any help, I'd really appreciate it. Thanks.

-Andrew

Post by **jblackburn** » 07 Oct 2012, 00:18

It sounds like either an air leak in a turbo/intercooler hose or a bad mass airflow sensor to me.

Post by **zulu-v40** » 07 Oct 2012, 09:09

*As you already deduced, the long crank time could be suggestive of a faulty Fuel Pressure Regulator. When I replaced mine, the car started up right away.
*You could try cleaning the Mass Air Flow sensor with MAF spray. Be careful not to actually touch the little sensor. Let it dry out before reinstalling. Inspect the wiring on the electronic connector for faults.
*After reading further about the P0107 code, a faulty MAP sensor (9125462) could be what's causing the long crank times and stumbling.
*Before blaming the MAP sensor, check for vacuum leaks like jblackburn suggested. Maybe a hose that should be sending air to the sensor is disconnected.

AGSchear · Post by **AGSchear** » 07 Oct 2012, 09:59

Thanks j and zulu. I'll start the repairs by checking to see if there are any hose leaks or if one has come loose. To be honest, I'm more concerned that I get the car starting and back on the road, and less concerned (at least at the moment) with the long crank times and rough idle.

Someone else has told me about an identical problem with an 01 S40, and the FPR was the culprit. Before I go to work, though, I'm certainly going to read up some more on what the MAP and MAF sensors are and think about why the OBDII might be giving me these codes.

mbreed · Post by **mbreed** » 08 Oct 2012, 08:39

You can pull the vacuum line off the fuel pressure regulator and sniff for gas in the regulator. If you smell gas its bad.

Post by **s40year2000** » 22 Dec 2015, 11:46

OP, how did you resolve your problem? I'm having the exact same issue with my 2000 s40 turbo. Thanks for your contribution!